PentestGPT is an open-source penetration testing agent that points a large language model at a target and lets it work. In its default mode it runs recon, then exploit, then walkthrough, each stage feeding the next. Switch it to pentest mode and the stages become asset discovery, vulnerability identification, report. No human sits in the loop.
The agent drives Claude Code or Codex, runs the tools, and decides what to try next. Gelei Deng and colleagues published the original version at USENIX Security 2024.
What you install
Python 3.12+, the uv
package manager, and two authenticated command-line tools: Claude Code and Codex. The Docker image bundles both CLIs so you log in once, the tokens land in volumes, and the logins survive container recreation. Codex login cannot be pre-seeded, because ChatGPT refresh tokens are single-use, so the OAuth callback gets forwarded through socat instead. That detail matters the first time you try to bake an image for a team.
The older design survives as pentestgpt-legacy
. It runs three cooperating LLM sessions, one reasoning, one generating, one parsing, that together maintain a Pentesting Task Tree while you drive the session interactively.
This human-in-the-loop mode talks natively to more providers than the autonomous pipeline does: OpenAI, Anthropic, Google Gemini, DeepSeek, xAI, Qwen, Moonshot, and local models through Ollama. The model registry was web-verified in June 2026, which is an admission that model IDs go stale. A built-in smoke test live round-trips every configured model and prints a pass/fail matrix, which is worth running before you trust the list.
Check the telemetry before you point it at a client
PentestGPT sends anonymous usage data to a Langfuse project by default: session metadata such as target type, duration, and completion status, which tools ran, and the fact that a flag was found. Command outputs, credentials, and flag values are never transmitted. That distinction is the one your client’s counsel will care about, and opting out takes either a command line flag or an environment variable.
PentestGPT is available for free on GitHub.
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